This application is based upon and claims the benefit of priority from the prior Japanese Patent Applications No. 11-251512, filed on Sep. 6, 1999; and No. 11-307078, filed on Oct. 28, 1999, the entire contents of which are incorporated herein by reference.
The present invention relates to a code-reading apparatus configured to be used for manual scanning of recording media, such as paper sheets, on which data including audio data, image data, and text data is recorded as codes that can be optically read by manual scanning, thereby allowing the codes to optically read and to reproduce the data.
U.S. Pat. No. 5,896,403 proposes a technique that allows various types of data including audio data, image data, and text data to be printed and recorded on recording media, such as paper sheets, as optically readable codes that can be manually scanned and read.
FIG. 1 shows a physical format of an optically readable dot code disclosed in the above-referenced U.S. Pat. No. 5,896,403. A dot code 1 is basically composed of multiple rectangular bocks 2 that are two-dimensionally arranged to be adjacent to each other.
Each of the blocks 2 is composed of a data-dot pattern section 3, markers 4, and a block-address pattern section 5. The data-dot pattern section 3 contains data items that are sectional according to the individual blocks of various types of data, such as audio data, in a predetermined arrangement of dot images of white dots and black dots that correspond to xe2x80x9c0xe2x80x9d and xe2x80x9c1xe2x80x9d that represent values of the aforementioned sectional data. Each of the markers 4 is composed of a predetermined number of consecutive black dots and are arranged at each of four corners of the individual bocks 2. The markers 4 thus arranged are used as reference points that allow detection of the individual dots (data dots) in the data-dot pattern section 3. The block-address pattern section 5 comprises error-detecting symbols and error-correcting symbols. The block-address pattern section 5 is arranged between the markers 4 to allow identification in reading of the multiple bocks 2, each of which is unique in the contents.
In FIG. 1, the vertical and horizontal lines in the block 2 are virtual lines drawn for convenience of indicating positions of the individual dots. Also, in FIG. 1, the black dots are recorded, while the white dots are not recorded; and portions of the white dots are shown in the ground color of the recording medium.
FIG. 2 shows an electric-function block configuration of a reading apparatus for use of manual scanning and optical reading of the dot code 1.
The reading apparatus is configured of at least an image pickup section 6, a binarizing section 7, a binarized image memory 8, a reconstituting section 9, a demodulating section 10, and a reproducing section 11. The image pickup section 6 comprises an illuminating section making of a light-emitting device (LED) or the like and being provided for illuminating the dot code 1, an optical system for imaging light reflecting from the dot code 1 and an area sensor, such as a charge-coupled device (CCD), for picking up the imaging light that is provided from the optical system. The binarizing section 7 uses a predetermined binarizing threshold and thereby binarizes an image signal outputted from the image pickup section 6. The binarized image memory 8 stores binarized image data which is binarized by the binarizing section 7. The reconstituting section 9 reads the binarized image data stored in the binarized image memory 8, thereby detects the dots, assigns one of the values xe2x80x9c0xe2x80x9d and xe2x80x9c1xe2x80x9d to each of the detected dots, and outputs data thereof. The demodulating section 10 demodulates the data outputted from the reconstituting section 9. The reproducing section 11 performs processing such as error processing and expansion processing, thereby reproducing the original data, such as the audio data, and outputting the reproduced data.
As shown in FIG. 1, the overall size of the dot code 1 is larger than a view field 6A of the image pickup section 6. However, the image pickup section 6 moves in the scanning direction as indicated by an arrow shown in the figure, and serially picks up section by section for the dot code 1, thereby allowing the whole dot code 1 to be read out.
In other words, although the whole dot code 1 cannot be picked up in one shot (one frame), when data dot patterns and block address patterns thereof can be read in units of the blocks, data of the individual blocks can be collected according to the block addresses, and the original data can thereby be reconstituted. In this way, code-reading can be implemented by manual scanning.
The reconstituting section 9 reads binarized image data stored in the binarized image memory 8 and thereby detects each of the aforementioned dots. The reconstituting section 9 first locates the marker 4, then references the centroid position of the marker 4 that has been located, and thereby obtains a dot-reading reference position. Subsequently, from the dot-reading reference position, the reconstituting section 9 detects a dot-reading point for reading each of the dots arranged in the data-dot pattern section 3, determines whether the detected dot-reading point is white or black, assigns one of the values xe2x80x9c0xe2x80x9d and xe2x80x9c1xe2x80x9d thereto, and outputs the corresponding data.
Such being the configuration, the dot code is printed and recorded with high-density print quality. Therefore, even if the print included some geometrical skews, read-out thereof would be able to be appropriately implemented.
For data such as audio data inputted as a recording object, modulation is preliminarily performed at printing and recording of the dot code 1. Thus, the demodulating section 10 performs processing that returns the modulated data to the state of original data, that is, to the premodulation state.
Specifically, the aforementioned modulation is preliminarily performed to facilitate the detection of the marker 4 in the reconstituting section 9. The modulation is performed so that the number of consecutive black dots in the data-dot pattern section 3, which differentiates the individual dots in the data-dot pattern section 3 from the marker 4, resultantly becomes smaller than the number of the consecutive black dots.
For example, suppose the maximum diameter of the marker 4 is equivalent to the size allowing five pieces of the black dots to be printed and recorded in the data-dot pattern section 3 are adjacently arranged in a predetermined direction. In this case, the modulation is performed for data such as audio data inputted as described above so that the number of consecutive black dots in modulated data (that is, after the modulation processing is performed) becomes smaller than five.
The individual configuration members are packaged in, for example, a pen-shape casing, thereby allowing manual operation to be performed for optical reading of the dot code 1 printed and recorded on a sheet-like recording medium, such as a paper sheet.
Specifically, as shown in FIG. 3, a reading opening provided is on an end portion of a reading apparatus 12, is positioned so as to be in contact with a recording medium 13, and is moved in a manner of tracing the dot code 1 printed and recorded on the recording medium 13 in the scanning direction, thereby outputting, for example, sounds.
As described above, according to the reading apparatus described above, easy manual operation allows optical reading to be implemented for the code recorded on the recording medium. Compared to a reading apparatus that requires a recording medium to be fitted in a predetermined position and that mechanically (i.e., automatically) operates to read a code recorded on the recording medium, handiness in handling of the above-described apparatus is further improved, and also, the usability thereof is significantly improved.
Thus, the reading apparatus is advantageous with regard to the manual scanning. At the same time, however, it cannot be denied that the manual scanning is unstable because of its nature. When scanning is performed in a condition that is worse than a predetermined condition, the same reading apparatus produces a disadvantage in that the original data cannot be reproduced, thus remaining the antinomy problems to be held pending solution.
A measure for solving the problems that can be considered is that the reading apparatus is configured to be capable of feeding back to a user regarding why a condition of read-out scanning actually performed is wrong. If causes for errors can be fed back to the user, it can be expected that the user would be careful to prevent recurrence of the errors in the future operation. It can be expected that this results in reduction of operational errors.
U.S. Pat. No. 5,719,886 discloses a technique of warning a user when scanning is performed in a state where a reading apparatus is off a code intended to be read out.
However, according to the technique disclosed in the aforementioned patent, although warnings are issued for errors that are caused by scanning performed in a state where the reading apparatus is erroneously off the code, the actual causes for the errors are not clear. This offers difficulty in knowing whether a warning was issued because scanning of a code intended to be read out was incompletely terminated or because scanning speed was so high that a block or blocks in the code were omitted in scanning.
Thus, since the user is given no way to know why the condition of actual read-out scanning is wrong, the user has no way to appropriately reflect the wrong condition in the future read-out scanning. From this viewpoint and for users to improve their skill of read-out scanning, the above-described measure cannot be evaluated to be sufficient to solve the above-described problems.
The present invention is made under the above-described circumstances. Accordingly, an object of the invention is to provide a code-reading apparatus that allows advantages of a reading apparatus to be even more enjoyed, the reading apparatus being capable of determining states of code-read-out scanning and appropriately feeding the states back to a user as guidance information, thereby allowing manual scanning to be implemented.
According to an aspect of the present invention, there is provided a code-reading apparatus comprising:
reading means allowing manual scanning to optically read a code from a recording medium having data recorded as the code that is optically readable, the code comprising a plurality of blocks provided for defining a read unit of the code and arranged at least in a scanning direction, and each of the blocks comprising block-address information indicating an address of each of the blocks in the code;
block-address-information-obtaining means for obtaining the block-address information from each of the blocks read out by the reading means;
scanning-state-determining means for determining a scanning state of manual scanning performed for the code along the scanning direction according to an obtained pattern in obtaining the block-address information obtained by the block-address-information-obtaining means; and
notifying means for performing predetermined notification according to a result of determination performed by the scanning-state-determining means.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.